crockford



2 Sheets-Sheet 1.

(No Model.)

A. H. GROGKFORD.

PNEUMATIC TIRE.

No. 587,075. Patented July 27, 1897.

THE Noah's PETERS co. Pno'fou'mu, wAsnmmcn, n cy (No Model.) 2Sheets-Sheet 2. A. H. OROGKPORD.

PNEUMATIC TIRE. No. 587,075. Patented July 27, 1897.

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UNITE TATES ATENT Fries,

ALFRED H. CROCKFORD, OF DARTFORD, ENGLAND.

PNEUMA'l'IC TIRE.

SPECIFICATION forming part of Letters Patent No. 587,075, dated. July27, 1897.

Application filed March 13, 1896. Serial No. 583,271. (No model.)

To a-ZZ whom it may concer I Be it known that I, ALFRED HENRY ORooK-FORD, engineer, a citizen of the United States of America, residing atDartford, England, have invented certain new and useful Improvements inPneumatic Tires, of which the following is a specification.

My invention relates to pneumatic tires of .the kind or'class known asself-healing the same, partly in vertical section, showing theconditions existing while in motion. Fig. 3 is a vertical sectionthrough a portion of the air'tube at the valve.

Attempts have heretofore been made to attain the desired end byintroducing materials of certain kinds into pneumaticiires with theobject of sealing any punctures that may be made therein, but so far asI am aware no material has yet been proposed which will satisfactorilyaccomplish the desired result.

My invention consists in the combination, with the air-chamber of apneumatic tire, of a suitable quantity of bran mixed with water or othersuitable liquid in or about in th eproportions hereinafter specified.

I have discovered that bran, when mixed witlrwater or other suitableliquid, is well adapted for the purpose of myinvention, as it is light,will not dissolve in the water, and contains a proportion of gluten oradhesive matter, which causes the pieces to adhere to some extent toeach other and to the interior surface of the air-tube withoutpreventing their being carried around with' the water. Moreover, whilethe wheel is in motion the water serves to moisten the bran and thusimprove its action in closing the pores or punctures and also to carryor sweep the .bran around the interior of the said tube and insure theefficient distribution thereof, under the action of the centrifugalforce, over the inner surface of the tread portion of the said tube. Isometimes mix a small quantity of size or similar glutinous substancewith the water which I force into the said tube.

I find it advantageous to introduce into the air-tube about one-halfpint to one pint of bran,'and a sufficient quantity of water or othersuitable liquid should be forced into the same to prevent theaccumulation of the bran at any one part of the tube. I find that withthe quantity of bran above stated about half a pint of water is enoughfor the purpose.

It is well known that when ordinary pneumatic tires are inflated theinternal air-pressure diminishes in a longer or shorter space of time,either by reason of the porosity of the rubber of which the tube is madeand-the consequent gradual escape of the air through the same, or byreason of the slow leakage of the air th rough small or fine puncturestherein the existence and location of which it is not easy to ascertainor determine, or by reason of slow leakage at or around the valve.Moreover, when the tire is in use it is liable to be puncturedby'contact with sharp objects on the road in such a manner that it willcollapse and must be repaired before it can be again inflated. By myinvention I overcome-these difficulties and provide a pneumatic tirewhich when once inflated will not lose its in ternal pressure unless thevalve is opened for the purpose of deflating it or a puncture or out ofunusually large dimensions is made in thetire, the pores of the rubberbeing completely closed in my tire by the moistened bran, which alsoserves to automatically close punctures which would render anyordinarytire useless until repaired and effects this result so rapidlyand effectively as not to permit the accidental deflationof the tire.

In making a tire according to my said invention I find it advantageousto fit a piece of flexible rubber tubing on a projecting piece or nozzleformed on the inner .end of the pipe forming the body of the air-inletvalve, which piece of tubing is of such length as to extend to about thecenter of the air-space of the inner or air tube of the tire. Thispieceof tubing being flexible will not be liable to injure the air-tubeshould the latter be pressed down upon the end of it. Into the inner orair tube so constructed I introduce a suitable quantity of the bran,preferably before joining the ends IOO of the said tube to form theendless tube. I then, either before or after the outer cover or sheathhas been applied, force in through the valve, by means of a pump orinflator, a suitable quantity of water or suitable liquid to mix withand moisten the bran and insure the distribution thereof through thesaid tube while the wheel is rotating.

Any suitable sheath or cover can be used with the inner tube thus made.

When I- make my tire with an endless tubular sheath or cover, as abovedescribed, I thread the inner tube through the slit thercof,. thenintroduce the bran and unite the ends of the tube to form an endlesstube, and then close the slit in the sheath or cover and force in thewater or other liquid.-

In the accompanying drawings, a is the airtube.

Z) is the flexible rubber tube fitted upon the valve-tube e.

(Z indicates the bran and water, which while the wheel is in motion arethrown outward by centrifugal force, as shown in Fig. 2.-

e is the endless tubular cover or sheath, which is made with a slit 6 topermit the insertion of the inner tube a and the joining of the endsthereof.

My improved air-tube can be used with any suitable form of outer coveror sheath, or myimprovements can be applied to a one tube or hose-pipetire.

Although I prefer that the air-tube should be endless, my improvementsare also applicable to tires in which the inflatable tube is closed atboth ends.

Since my improved air-tube is much less liable than those hitherto madeto be punctured in such a manner as to require removal or withdrawal forrepairs, I can, if desired, in cases where an endless tubular sheath isemployed, join the two ends of the air-tube, after it has been drawninto said sheath, through the slit therein, so as to form an endlessair-tube in said endless tubular sheath.

I am aware that it has been heretofore proposed to insert in theair-chamber of a tire small pieces of oiled silk, rubber-coated fabric,sheet india-rubber, and like materials,

but such materials differ very greatly in character from bran and willnot fulfil the same functions as the bran. It has also been proposed tointroduce into the tire with the said small pieces of oiled silk or likematerials some lubricating substancesuch, for instance, as glycerin andwaterbut such lubricating substance was used only to coat the interiorsurface of the air-chamber and not, as the water is used in my improvedtire, to moisten the inclosed material and sweep it around theair-chamber, so as to properly distribute it throughout the interiorthereof. I am also aware that it has been heretofore proposed to stuff atire with bran to deaden the noise arising from a special constructionof rim or felly; but I am not aware that it has ever been proposed priorto the date of my invention to introduce into the air-chamber of thetire bran mixed with a liquid, such as water, in such quantities orproportions that when the wheel is rotated the bran will be carriedaround and distributed by the water, so that a puncture occurring at anypoint in the circumference of the tire will be closed by the bran.Moreover, bran has certain inherent qualities or properties whichpeculiarly adapt it, when properly moistened with water, for the purposeof stopping or closing punctures in pneumatic tires.

\Vhat I claim is- The combination, with the air-tube of a pneumatic tireof a mixture of bran with a liquid such as water contained in the saidair-tube, the bran and liquid being mixed in the proper proportions tosufficiently moisten the bran and to sweep the same around anddistribute it throughout said tube while the wheel is in motion,substantially as heretofore described.

In testimony whereof I have hereunto set my hand in presence of twosubscribing witnesses.

A. II. CROCKFORI).

\Vitnesses:

JOHN T. Kxownns, HENRY W. LYNDEN.

